/****************************************************************************
*porting form linux kernel
*****************************************************************************/


#ifndef _LINUX_LIST_H  
#define _LINUX_LIST_H  
  
//#if defined(__KERNEL__) || defined(_LVM_H_INCLUDE)  
  
//#include <linux/prefetch.h>  
  
 void prefetch(const void *x) {;}   
  
 void prefetchw(const void *x) {;}   
  
/* 
 * Simple doubly linked list implementation. 
 * 
 * Some of the internal functions ("__xxx") are useful when 
 * manipulating whole lists rather than single entries, as 
 * sometimes we already know the next/prev entries and we can 
 * generate better code by using them directly rather than 
 * using the generic single-entry routines. 
 */  
  
struct list_head {  
    struct list_head *next, *prev;  
};  
  
#define LIST_HEAD_INIT(name) { &(name), &(name) }  
  
#define LIST_HEAD(name) \  
    struct list_head name = LIST_HEAD_INIT(name)  
  
#define INIT_LIST_HEAD(ptr) do { \  
    (ptr)->next = (ptr); (ptr)->prev = (ptr); \  
} while (0)  
  
/* 
 * Insert a new entry between two known consecutive entries.  
 * 
 * This is only for internal list manipulation where we know 
 * the prev/next entries already! 
 */  
static  void __list_add(struct list_head *new,  
                  struct list_head *prev,  
                  struct list_head *next)  
{  
    next->prev = new;  
    new->next = next;  
    new->prev = prev;  
    prev->next = new;  
}  
  
/** 
 * list_add - add a new entry 
 * @new: new entry to be added 
 * @head: list head to add it after 
 * 
 * Insert a new entry after the specified head. 
 * This is good for implementing stacks. 
 */  
static  void list_add(struct list_head *new, struct list_head *head)  
{  
    __list_add(new, head, head->next);  
}  
  
/** 
 * list_add_tail - add a new entry 
 * @new: new entry to be added 
 * @head: list head to add it before 
 * 
 * Insert a new entry before the specified head. 
 * This is useful for implementing queues. 
 */  
static  void list_add_tail(struct list_head *new, struct list_head *head)  
{  
    __list_add(new, head->prev, head);  
}  
  
/* 
 * Delete a list entry by making the prev/next entries 
 * point to each other. 
 * 
 * This is only for internal list manipulation where we know 
 * the prev/next entries already! 
 */  
static  void __list_del(struct list_head *prev, struct list_head *next)  
{  
    next->prev = prev;  
    prev->next = next;  
}  
  
/** 
 * list_del - deletes entry from list. 
 * @entry: the element to delete from the list. 
 * Note: list_empty on entry does not return true after this, the entry is in an undefined state. 
 */  
static  void list_del(struct list_head *entry)  
{  
    __list_del(entry->prev, entry->next);  
    entry->next = (void *) 0;  
    entry->prev = (void *) 0;  
}  
  
/** 
 * list_del_init - deletes entry from list and reinitialize it. 
 * @entry: the element to delete from the list. 
 */  
static  void list_del_init(struct list_head *entry)  
{  
    __list_del(entry->prev, entry->next);  
    INIT_LIST_HEAD(entry);   
}  
  
/** 
 * list_move - delete from one list and add as another's head 
 * @list: the entry to move 
 * @head: the head that will precede our entry 
 */  
static  void list_move(struct list_head *list, struct list_head *head)  
{  
        __list_del(list->prev, list->next);  
        list_add(list, head);  
}  
  
/** 
 * list_move_tail - delete from one list and add as another's tail 
 * @list: the entry to move 
 * @head: the head that will follow our entry 
 */  
static  void list_move_tail(struct list_head *list,  
                  struct list_head *head)  
{  
        __list_del(list->prev, list->next);  
        list_add_tail(list, head);  
}  
  
/** 
 * list_empty - tests whether a list is empty 
 * @head: the list to test. 
 */  
static  int list_empty(struct list_head *head)  
{  
    return head->next == head;  
}  
  
static  void __list_splice(struct list_head *list,  
                 struct list_head *head)  
{  
    struct list_head *first = list->next;  
    struct list_head *last = list->prev;  
    struct list_head *at = head->next;  
  
    first->prev = head;  
    head->next = first;  
  
    last->next = at;  
    at->prev = last;  
}  
  
/** 
 * list_splice - join two lists 
 * @list: the new list to add. 
 * @head: the place to add it in the first list. 
 */  
static  void list_splice(struct list_head *list, struct list_head *head)  
{  
    if (!list_empty(list))  
        __list_splice(list, head);  
}  
  
/** 
 * list_splice_init - join two lists and reinitialise the emptied list. 
 * @list: the new list to add. 
 * @head: the place to add it in the first list. 
 * 
 * The list at @list is reinitialised 
 */  
static  void list_splice_init(struct list_head *list,  
                    struct list_head *head)  
{  
    if (!list_empty(list)) {  
        __list_splice(list, head);  
        INIT_LIST_HEAD(list);  
    }  
}  
  
/** 
 * list_entry - get the struct for this entry 
 * @ptr:    the &struct list_head pointer. 
 * @type:   the type of the struct this is embedded in. 
 * @member: the name of the list_struct within the struct. 
 */  
#define list_entry(ptr, type, member) \  
    ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))  
  
/** 
 * list_for_each    -   iterate over a list 
 * @pos:    the &struct list_head to use as a loop counter. 
 * @head:   the head for your list. 
 */  
#define list_for_each(pos, head) \  
    for (pos = (head)->next, prefetch(pos->next); pos != (head); \  
            pos = pos->next, prefetch(pos->next))  
/** 
 * list_for_each_prev   -   iterate over a list backwards 
 * @pos:    the &struct list_head to use as a loop counter. 
 * @head:   the head for your list. 
 */  
#define list_for_each_prev(pos, head) \  
    for (pos = (head)->prev, prefetch(pos->prev); pos != (head); \  
            pos = pos->prev, prefetch(pos->prev))  
              
/** 
 * list_for_each_safe   -   iterate over a list safe against removal of list entry 
 * @pos:    the &struct list_head to use as a loop counter. 
 * @n:      another &struct list_head to use as temporary storage 
 * @head:   the head for your list. 
 */  
#define list_for_each_safe(pos, n, head) \  
    for (pos = (head)->next, n = pos->next; pos != (head); \  
        pos = n, n = pos->next)  
  
/** 
 * list_for_each_entry  -   iterate over list of given type 
 * @pos:    the type * to use as a loop counter. 
 * @head:   the head for your list. 
 * @member: the name of the list_struct within the struct. 
 */  
#define list_for_each_entry(pos, head, member)              \  
    for (pos = list_entry((head)->next, typeof(*pos), member),   \  
             prefetch(pos->member.next);         \  
         &pos->member != (head);                     \  
         pos = list_entry(pos->member.next, typeof(*pos), member),   \  
             prefetch(pos->member.next))  
  
/** 
 * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry 
 * @pos:    the type * to use as a loop counter. 
 * @n:      another type * to use as temporary storage 
 * @head:   the head for your list. 
 * @member: the name of the list_struct within the struct. 
 */  
#define list_for_each_entry_safe(pos, n, head, member)          \  
    for (pos = list_entry((head)->next, typeof(*pos), member),   \  
        n = list_entry(pos->member.next, typeof(*pos), member);  \  
         &pos->member != (head);                     \  
         pos = n, n = list_entry(n->member.next, typeof(*n), member))  
  
/** 
 * list_for_each_entry_continue -       iterate over list of given type 
 *                      continuing after existing point 
 * @pos:        the type * to use as a loop counter. 
 * @head:       the head for your list. 
 * @member:     the name of the list_struct within the struct. 
 */  
#define list_for_each_entry_continue(pos, head, member)         \  
    for (pos = list_entry(pos->member.next, typeof(*pos), member),   \  
             prefetch(pos->member.next);         \  
         &pos->member != (head);                 \  
         pos = list_entry(pos->member.next, typeof(*pos), member),   \  
             prefetch(pos->member.next))  
  
//#endif /* __KERNEL__ || _LVM_H_INCLUDE */  
  
#endif 



